Article stringing machines



Aug. 23, 1966 Filed May l5, 1963 H. A. IMHOF ARTICLE STRINGING MACHINES4 Sheets-Sheet l Allg- 23 1966 H. A. IMHOF ARTICLE STRINGING MACHINES 4Sheets-Sheet 2 Filed May 15, 196s Aug 23. 1966 H. A. IMHOF 3,267,894

ARTICLE STRINGING MACHINES Filed May 13, 1963 4 Sheets-Sheet 5 75 36 c??Aug. 23, 1966 H. A. IMHOF ARTICLE STRINGING MACHINES 4 Sheets-Sheet 4Filed May 13, 1963 United States Patent O 3,267,894 ARTICLE STRINGINGMACHINES Herman A. Imhof, Hamilton, Mass., assignor to United ShoeMachinery Corporation, Boston, Mass., a corporation of New Jersey FiledMay 13, 1963, Ser. No. 279,749 8 Claims. (Cl. 112-104) This inventionrelates to improvements in article stringing machines and moreparticularly to a solution of problems which arise in Such priormachines as a result of operating upon highly resistive materials.

In an article Stringing machine such as that disclosed in applicationSerial No. 117,219, filed June 15, 1961, in the names of Charles P.Cardani et al., now U. S. Patent No. 3,142,896, as further improved bythe disclosures of my copending United States applications for UnitedStates Letters Patent Serial No. 184,804 filed April 3, 1962, and nowU.S. Letters Patent No. 3,207,106 and Serial No. 202,552 tiled I une 14,1962, and now U.S. Letters Patent No. 3,174,448, articles of merchandiseor workpieces such as pairs of shoes are clamped one on each side of apedestal .and thereafter strung together with or without the coincidentattachment of a tag lbearing size and price indicia. In the Stringingoperation the leading end of the strand is carried through the articlesby a curved eyepointed needle which iS then retracted slightly to form abulge in the Strand. The `'bulge is gripped 'by a pincer whichthereafter manipulates the leading end while another pincer carries thetrailing end to form a closed and sealed loop passing through thearticle or articles. The reliable formation of the bulge in the leadingend to be gripped by the .pincer is necessary to the dependableoperation of the machine since failure of the strand to bulge results inthe strand being missed by the pincer. When the article being Strung iScomposed of highly resistive materials a number of factors combineeither to prevent the Aformation of the bulge or to eliminate it beforeit can be effectively gripped and brought Iunder the control of thepincer.

It is accordingly an object of the invention to provide improved meansfor controlling more reliably the formation of a Ibulge in the leadingend of the Strand in article Stringing machines, and for retaining thebulge until it is gripped by a pincer of the machine.

Another object is to provide novel means for supporting a workpieceagainst displacement under the force of needle penetration when theworkpiece is composed of more resistive materials than have heretoforebeen operated on by Stringing machines.

Another object of the invention is to improve the clamping of articlesin Stringing position.

Still a further object is to minimize deformation of the needle andavoid its breakage runder the forces of penetrating resistive materials.

A more limited but important object is to reinforce the needle withoutimposing frictional drag upon it.

In the achievement of the foregoing objects a feature of the inventionrelates to a lock installed for preventing movement of a clamp Similarto that employed in the machines of the above-identified application.When the prior machines are being employed for Stringing together pairsof articles such as shoes one shoe iS clamped against each Side of thepedestal and the needle thereafter penetrates both shoes to carry theleading end of the Strand through both shoe uppers. In penetrating thelirst shoe little diiliculty is experienced with the related clamp sincethe thrust of the needle presses the Shoe toward the pedeStal. Thethrust of the needle in penetrating the second Shoe, however, isresisted by a clamp aS the needle pushes the Second shoe away from thepedestal. The left clamp which holds the Second article against the ICCpedestal does So under a spring force and when the force required forthe needle to penetrate the article exceeds the force of the spring, thearticle follows the clamp until the thrust is relieved either at thetime that needle penetration is completed or later in the operatingcycle of the machine when the needle is partially retracted lfor thepurpose of forming a lbulge to be gripped by a pincer. In either eventthe effect of clamp deflection and return, in accordance with the forcebeing exerted by the needle upon the workpiece, is to prevent theformation of the necessary bulge in the leading end of the strand, andconsequently preventing the reliable gripping of the leading end of thestrand by a pincer for subsequent manpulation. As a result of the lock,.according to the present invention, the needle thrust absorbing clampis retained in article gripping position Without Substantiallyincreasing the spring force which would add materially to operatorfatigue.

According to another feature of the invention, an auxiliary needle guideprevents excessive needle deflection while penetrating resistivematerials. The auxiliary guide is coupled to a needle drive Sector onthe machine in such a way that there is no relative motion between theguide and the needle while the needle is being subjected to deformingforces. The auxiliary needle guide driving means comprising a pin andball arrangement positions the guide at the time that the first articleis being penetrated, so that the unsupported length of needle isapproximately half of the length.

Numerous advantages and features of the invention will be betterunderstood from the following description of an illustrative embodimenttaken in connecton with the accompanying drawings in which,

FIG. 1 is a fragmentary view in la left side elevation of an articleStringing machine, including a clamp and lock according to the presentinvention;

FIG. 2 is a fragmentary view in front elevation of a pedestal andarticle clamps in which one of the clamps is provided with the lock ofFIG. 1, and in which the needle is provided with an auxiliary guide;

FIG. 3 is a View of devices related to the needle including theauxiliary guide of FIG. 2 with the parts shown in exploded relationship;

FIG. 4 is a fragmentary plan View showing a bridge for reenforcing thepedestal;

FIG. 5 is a detail view in front elevation and partly in Section Showingclamp operating connections and the clamp lock of FIGS. 1 and 2;

FIG. 6 is a detail perspective view Showing the construction of the workclamps;

FIGS. 7 and 8 are fragmentary views in front elevation showing relativepositions of the needle and auxiliary guide at the Start of needlepenetration through a iirst article and after complete penetration oftwo articles by the needle respectively; and

FIG. 9 is a Schematic view on an enlarged scale Showing the formation ofa bulge in the leading end of the Strand and the gripping of the bulgedportion of Strand by a pincer.

Referring to FIGS. 1 and 2, the present machine includes a subframe 10and a pedestal 12 corresponding respectively to the subframe and thepedestal 256 of the above-identified Cardani et al. application. As inmy application Serial No. 202,552 there is also included in the machinea curved eye-pointed needle 14 mounted in a needle carrier 16 andprovided with a needle guide 18 which will be referred to in -thepresent Specification aS the main needle guide. The needle carrier 16and the main guide 18 are both journaled on a short shaft 20 ixedlysupported in the subframe 10 and the needle carrier is driven to actuatethe needle through a Work penetrating Stroke through connectionsincluding an integral pinion 2-2 meshing with a cam actuated sector 24.

A typical operation of the machine consists of penetrating a pair ofarticles fragmentarily illustrated in the drawings as a pair lof shoes26, 28 held against the left and right side of the pedestalrespectively, by clamp pads 30 and 32. In penetrating -the articles theneedle carries the leading end of a strand 34 to the position depictedin FIG. 8 and by being withdrawn slightly causes the formation of abulge in the leading end of the strand as shown in PIG. 9 to rbe grippedby a iirst or left pincer indicated generally at 36. The needle 14 isthen completely withdrawn and. a second or right pincer indicatedgenerally at 38 grips the strand 34 between the iirst penetrated articleand the eye of the needle before the strand is severed by a severingdevice, indi-cated generally at 40 in FIG. 4. Thereafter ythe ends -ofthe severed strand, the length of which may be controlled, as disclosedin my application Serial No. 184,804, or as set -forth in the Cardani etal. application, are manipulated to form a closed loop by forming bightsfrom the end portions about an eyeleting lspindle 42 mounted on thepedestal 12. Thereafter the two hights are secured together by means ofan eyelet which may also couple a tag to the strand, the eyeletclinching being -accomplished by an eyeleting tool 44 cooperating withthe spindle 42, as is already well understood.

Workpieces operated upon 'by the present machine frequently includelaminated Acounter materials which are much more resistive to needlepenetration than ordinary shoe uppers heretofore considered difficult topenetrate. As shown in FIG. 9 such a workpiece may be in the form of animitation Shearling slipper including an upper 46 of leather, a thicklaminated counter 48 and a heavy pile imitation Shearling lining 50.This type of workpiece is highly resistive to penetration by the needle14 and in prior machines has resulted in unreliable 'bulge formation inthe leading end of the strand. A part of this diflculty is traceable todeflection of the pedestal in the direction of needle penetration. Inthe present machine this deflection has been cured by .providing abridge between the subframe and the pedestal 12 in the form of a strap52 secured by screws 54 to the subframe 10 and having its other endformed with a shallow slot the walls of which embrace the thickness ofthe rearward end of the pedestal. The screws 54 pass through the strapand an abutment member for operating the severing device 40 and arethreaded into an integral ear of the subframe.

Another diliiculty in prior machines when operating upon highlyresistive materials is that the clamp pad corresponding .to that4designated by the reference numeral 30 is pushed away from the pedestalby the thrust of the needle. The movement of the left clamp in priormachines is partly the result of deformation of the clamp pad supportingstructure. As seen in FIGS. 2, 5 and 6 particularly, the supportingstructure lfor both the clamp pads 30 and 32 have been substantiallyreenforced. In the present machine the pad 30 is pivoted near the lowerend of a slotted arm 58 formed integral with the forward end of `a body60 of irregular cross section to adapt to the highly crowded environmentof this area of the machine. The =body 60 is in -turn integral with aprojection 62 bored to fit lthe shaft 20. The projection 62 extends as asleeve -64 having a considerable length on the shaft and the parts 62and `64 are retained against endwise motion between a shoulder on `theshaft and a snap Aring 66 iitted to the rearward end of the shaft. Theparts 58, 60, 62 and 64 may be in the form of a steel weldment if greatcare is exercised to prevent exure at the joints -or alternatively maybe machined from a single piece of metal. Similarly, the clamp pad 32 ispivoted at the lower end of a slotted arm 68 depending from a body 70formed with a projection 72 having a rearwardly extending sleeve portion74 bored to -be received 0n the sleeve 64 and also retained by the snapring 66.

For urging the cla-mp pads 30 and 32 into pressing engagement with thework pieces there are provided, as in prior machines, a pair of tensionsprings stretched lbe- -tween each clamp body and a lixed anchor point.Thus there is associated with the body 60 a spring 76 connected to a pin78 extending rearwa-rdly from the body 60. Similarly, there is a spring80 connected to a pin 82 extending from the body 70 for urging the clamppad 32 into engagement with its related workpiece.

For causing opening of the clamp pads to receive and release workpiecesthere is provided a T-shaped slide mounted actuator 84 connected as inprior machines with la treadle. The upper bar portion of the actuator 84when raised engages a pair of rolls S6, 88 mounted respectively, on thepins 78 and 82 for causing the opening of the clamps against the springbias. When the clamp operating treadle is released, a tension spring 90causes the actua-tor 84 to move away from the rollers 86, 88 so thatclamping pressure is applied to the pads 30, 32 by the springs 76, 80.

In prior machines the article in the position of the shoe 26, whilebeing penetrated by the needle, is pushed by the force of needlepenetration against the clamp pad and away from the pedestal, therestraining force being provided solely by the clamp spring which isnecessarily limited in order to minimize fatigue to the operator inoperating the clamp treadle. There is provided for the clamp pad 30 inthe present machine a lock in the form of a wedge 94, seen in FIGS. 1 to6. The wedge 94 is formed integral with a slide 96 of T-shaped crosssection and vertically movable in a guideway formed for the purpose in ablock 98 iixedly supported on the rearward surface of the pedestal andalso providing a guideway for the Iactuator 84. The wedge 94 is urgeddownwardly by a tension spring 100 stretched between the lower end ofthe slide 96 and a fixed anchor block 102.

A simple but effective connection is provided for imparting a releasingmotion to the wedge before the clamps are opened and a locking motionafter the clamps are closed. As in the prior machine of my applicationSerial No. 202,552 the depressing of the spindle 42 is accomplished bythe same treadle which causes the opening of the clamps and there isprovided a delay so that the spindle is lowered before the clamps beginto open. For this purpose the lower end of the actuator s bifurcated toreceive the thickness of a link 104 which is raised by treadle action tocause the opening of the clamps. The link 104 carries a pin 106 passingthrough slots 108 in the lower end of the actuator 84 so as to providethe necessary lost motion between the lowering of the spindle 42 and theopening of the clamps. It is thus seen that as the link 104 rises thereis no motion imparted to the actuator 84 until the pin 106 reaches theupper end of the slot 108. The pin 106 extends to the left of theactuator as seen in FIG. 5 and its outward end underlies a projectingportion of the slide 96 so that as the link 104 is raised, but beforethere is any motion imparted to the actuator 84 the Wedge 94 is raisedout of contact with the roll 86.

It is seen from the foregoing that the bridge 52 prevents deflection ofthe pedestal 12 and that displacement of the clamp pad 30 as a result ofdistortion of the clamp body from the force of needle penetration hasbeen largely eliminated when operating upon materials within theresistivity limits of the machine by substantially stiiening the clamppad supporting structure. In addition the wedge 94 which has a faceengaging the roll 86 and dening with a vertical plane an angle ofapproximately 10 provides a substantial mechanical advantage to theforce of the spring 100 in preventing Aswinging motion of the left clampassembly including the pad 30 under the force of needle penetration. Thewedge 94 is advantageous in that it provides effective locking actionwithout materially increasing the force required by the operator uponthe clamp operating treadle.

As already explained another factor which contributes to the diicultiesexperienced in forming a bulge from the leading end of the strand inprior machines is deflection of the needle under the force ofpenetration, the needle tending to assume a smaller radius of curvatureso that its midportion is deected outwardly from its normal unstressedposition. Under severe conditions this deection results in frequentneedle breakage. In the present machine, the midportion of the needle isretained against outward deflection by an auxiliary guide 110 having anopening through which the needle passes freely and mounted for motionconcentrically with the needle. It is extremely important to avoidadditional cam actuated elements in the vicinity of the needle becauseof the already crowded conditions and the further complications thatsuch connections would cause. At the same time it is necessary toachieve relative motion between the auxiliary guide 110 and the needle14, and the relative motion must further be achieved at a time when theneedle is subject to little or no deformation caused by the force ofpenetrating a workpiece. For this purpose there is provided a pair ofdetent driving connections between the needle carrier 16 and theauxiliary guide 110, each connection consisting of a pin and a springpressed ball. As seen in FIGS. 2 and 3 which depict the rest conditionof the machine, the rst auxiliary guide driving connection which impartsmotion to the guide as the needle 14 moves toward the workpiece 2S,includes a pin 112 pressed into and projecting forwardly from a radiallyextending portion of the needle carrier 16. The pin 112 passes throughan arcuate slot 114 in the guide 110 and provides the driving connectionby engaging a ball 116 pressed radially out- Wardly by a spring 118. Thepin 112 performs the additional function of anchoring one end of atorsion spring 120 which urges the main guide 18 to advance toward theworkpiece 28 in step with the needle 14. The main guide 18 travels withthe needle until the guide reaches the position of FIG. 8 in which itengages a stop 122 on the pedestal 12 and thereafter the needlecontinues to move through the guide 1S. It will be noted that the mainguide 18, as seen in FIG. 7, is reaching its most advanced positiontoward the work at just about the time that the point of the needlecommences to penetrate a workpiece of average thickness held by theclamp 32. At this time in the machine cycle when the needle undergoesthe stress of penetrating the rst article the auxiliary guide 110 drivenfrom the needle carrier 16 through the connection 112, 116 is movingtoward the clamp pad 32 in step with the needle 14, there being norelative motion between the auxiliary guide and the needle. This absenceof relative motion between the needle and the auxiliary guide while theneedle is under stress, is important to avoid serious scoring, rapidwear and possible binding together of the needle and auxiliary guide.The needle and auxiliary guide continue to travel together until theauxiliary guide comes to rest against the back of the already-stoppedmain guide 18. A notch 123 formed in the guide 110 centralizes thestrand 34 with the needle and prevents the pinching of the strandbetween the two guides. At this point the pin 112 escapes from the ball116 and the needle continues in motion while the auxiliary guide remainsstationary. As may be judged from the relative positions of the guide 18and the auxiliary guide 110 on the one hand and the thickness of thepedestal 12, which determines the spacing between workpieces, the escapeof the pin 112 from the ball 116 occurs after the first .articleillustrated as the shoe 2S has been completely penetrated by the pointof the needle but before the needle engages the second article 26.

A second connection comprising a pin `124 pressed into the carrier 16and extending forwardly in spaced parallel relation with the pin 11-2and a b-all 126 pressed radially outwardly by a spring |128, is providedfor returning the needle guide 1 10 to its proper starting position forthe next operating cycle of the machi-ne.

As the auxiliary guide 110 reaches the position in which it is shown inFIG. 8, the pin 112 depresses the ball 116 and escapes. Shortlythereafter as the needle carrier 16 continues in motion the pin 1,24depresses the ball 126 and moves ahead of the ball in the clockwisedirection. iBut it will be noted that as `the shoe 28 is penetrated theauxiliary guide y1=10` is `at approximately the midpoint of theotherwise unsupported extent of needle length and -is moving with theneedle so that there is no :relative motion between the needle and theauxiliary guide. While the needle point is penetrating the shoe 26 rthehalf of the needle nearest the carrier 14 is sliding in a xed supportconsisting of the combination of the main guide 18 and the auxiliaryguide 110 and accordingly the danger of abrasive dama-ge to the needlesurface in contacting with the guides is substantially reduced becausethe load is distributed over a relatively large area.

As the needle having been rotated to form a bulge to be .gripped by thepincer 36 is retracted toward the position of IFIG. 2 the pin '124engages the ball 126 and |the auxiliary guide '110 is thereby carried ina counterclockwise direction with the `carrier 16. In order to reset theconnection 112, *116 for the next article penetrating stroke of theneedle there is provided a downwardly extending nger l130 dixedlymounted on the .frame in Iwhich the eyeleting tool 44 is slidablysupported. In proceeding in a counterclockwise direction duringretraction `of the needle 114, the auxiliary guide ,110 is carried untilit abuts the finger 13G. Thereafter the pin -124 which continues inmotion escapes from the ball f126 and the pin 112 also passes the ball|116 to be prepared for driving the auxiliary guide in the clockwisedirection during the next operation of the machine.

Very crowded -conditions .are encountered in the mounting of the mainand auxiliary guides yin effective positions. As may be seen in FIG. 3,the needle carrier is formed with a short cutaway forwardly extendinghub 132 and provided with a pressed oilless bronze bearing 134 theIinside diameter of which tits the shaft 20. The main guide 18 is boredto be received upon the bearing 134 and has a longer rearwardlyextending hub 136 cut away to cooperate with the cutaway hub 132 as willbe explained. The inside diameters of the two hubs 134, 136 are matchedand are received within the auxiliary guide 1110, so that the `guideI'1110 is free to pivot on the hubs. The cutaway section of the hub l134provides a radially extending surface 138 'which engages a surface 140on the hub y'136 to return the main guide 18 to the position depicted inFIG. 2 as the needle carrier 16 is returned to its inactive position.

Having thus described my invention what I claim as new and desire tosecure by letters Patent of the United States is:

1. An article Stringing machine comprising a pedestal, means for holdinga workpiece against the pedestal, a curved eye-pointed needle, a carrierupon which the needle is mounted to be oscillated to carry the leadingend of a strand through the workpiece and to retract, a main needleguide located near the point of the needle as the workpiece is beingpenetrated, an auxiliary needle guide for supporting the midportion ofthe needle, and a driving connection `for the auxiliary guide from theneedle carrier to impart motion to the guide in step with the needle atthe time of workpiece penetration.

2. An article stringing machine comprising a pedestal, means for holdinga workpiece against the pedestal, a curved eye-pointed needle, a carrierupon which the needle is mounted to be oscillated to carry the leadingend of a strand through the workpiece and to retract, a main needleguide located near the point of the needle as the workpiece is ybeingpenetrated, an auxiliary needle guide for supporting the midportion ofthe needle, and a driving connection ybetween the needle carrier and theauxiliary needle guide including a spring .pressed bal-l -in one memberanda pin in the other member.

3. An article `Stringing machine comprising a pedestal, means forholding a workpiece against the pedestal, a curved eye-pointed needle, acarrier upon which the needle is mounted to be oscillated to carry theleading end of a strand through the workpiece and lto retract, a mainneedle guide located near the point of the needle as the workpiece islbeing penetrated, .an `auxiliary needle xguide for supporting lthemidportion of the needle and a pair of connections for the auxiliaryneedle guide each including a spring pressed :ball in the needle guideand a pin in the carrier, the first driving connection being effectiveduring needle motion in a tirst direction and the other connection beingoperative 'for return-ing the auxiliary guide to its starting position.

4. An article Stringing machine comprising a pedestal, means Iforholding a workpiece against the pedestal, a curved eye-pointed needle, acarrier lupon Which the needle is mounted to be oscillated to carry theleading end of a strand through the workpiece vand .to retract, a mainneedle guide ylocated near the point of the needle as the workpiece is@being penetrated, an auxiliary needle guide for supporting themidportion of the needle, a irst conneet-ion between `the auxiliaryguide and the carrier including a spring pressed ball on the auxiliaryyguide and a pin mounted on Lthe carrier and positioned to engage theAball to impart motion to the auxiliary guide in step with the needlewhile the needle is penetrating the workpiece and a second connectionincluding 1a second spring pressed hall on the auxiliary guide and asecond pin on the car- Tier for returning the auxiliary guide to itsstarting position.

5. An article stringing machine comprising a pedestal, a curvedeye-pointed needle, means vfor oscillating the needle to carry theleading end of ya strand through a workpiece clamped against .thepedestal and to retract, a clamp kfor holding the workpiece against thepedestal and clamp locking means including a slide mounted wedge -forpreventing displacement of the clamp from its workpiece holding positionunder the thrust of the needle.

6. An article Stringing machine comprising a pedestal, a curvedeye-pointed needle, means for oscillating the needle to carry theleading end of a strand through workpieces clamped against the pedestaland to retract, a pair of 'work clamps the second one of which retainsone of the Workpieces in contact with vthe pedestal against the thrustof the needle, an actuator for opening the clamps, a locking Wedge forthe -second clamp yand a lost motion connection between the actuator andthe wedge for unlocking the Wedge before an opening motion is impartedto lthe clamps.

7. An larticle .Stringing machine comprising a pedestal, a curvedeye-pointed needle, means for oscillating the needle to carry theleading end of a strand through Workpieces clamped against the pedestaland `to retract, a pair of Work clamps the second one of Which retainsits related workpiece in contact with the pedestal against the :thrustof the needle, a locking wedge, :a spring urging the wedge into lockingengagement with .the second clamp, clamp opening connections and meansinterposed between the connecti-ons and the wedge for releasing thewedge from locking engagement before the clamps are opened.

8. An .article Stringing machine comprising a pedestal against which aworkpiece is 'held in `Stringing position, la curved eye-pointed needle,a carrier upon which the needle lis mounted to be oscillated to carryAthe leading end of the strand through the workpiece and to retract, aclamp holding the workpiece in contact with the pedestal against theforce of needle penetration, clamp locking means to prevent displacementof the clamp under the force of needle penetra-tion, a pincer forgripping 'a bulge formed in the leading end of the strand as the needleis retracted, a needle guide supporting a portion of the needle near thepoint, and an auxiliary guide coupled to the carrier for supporting anintermediate portion of Ithe needle whereby lthe bulge in the leadingend of the strand is formed reliably to be gripped by the pincer.

References Cited by the Examiner UNITED STATES PATENTS 3,166,035 1/1965Wiegand 112-104 X JORDAN FRANKLIN, Primary Examiner.

G. V. LARKIN, Assistant Examiner.

1. AN ARTICLE STRINGING MACHINE COMPRISING A PEDESTAL, MEANS FOR HOLDING A WORKPIECE AGAINST THE PEDESTAL, A CURVED EYP-POINTED NEEDLE, A CARRIER UPON WHICH THE NEEDLE IS MOUNTED TO BE OSCILLATED TO CARRY THE LEADING END OF A STRAND THROUGH THE WORKPIECE AND TO RETRACT, A MAIN NEEDLE GUIDE LOCATED NEAR THE POINT OF THE NEEDLE AS THE WORKPIECE IS BEING PENETRATED, AN AUXILIARY NEEDLE GUIDE FOR SUPPORTING THE MIDPORTION OF THE NEEDLE, AND A DRIVING CONNECTION FOR THE AUXILIARY GUIDE FROM THE NEEDLE CARRIER TO IMPART MOTION TO THE GUIDE IN STEP WITH THE NEEDLE AT THE TIME OF WORKPIECE PENETRATION. 